Seasonal variation of the surface boundary layer and the lower atmospheric boundary layer over boreal forests

对西伯利亚松林的水分和能量循环进行了分析，并与西伯利亚落叶松林的结果进行了比较。这些周期在两个林地之间的季节变化有显著差异。Jarvis类型电导模型的参数与在落叶松林中获得的参数相似。不仅使用我们的数据集而且使用已发布的数据集的Jarvis类型模型中的参数与使用全球网格数据集的气候变量之间存在明显的关系。这一结果表明，在相同的气候条件下，尽管植被类型不同，但生理反应可能是相似的。水分循环特征在0级山谷中进行了研究。当土壤水分较高时，林地蒸散量受风速空间分布的影响较大。另一方面，林下蒸发蒸散量不仅受风速的影响，还受土壤水分控制的蒸发效率的空间分布的影响。结果表明，局地环流对西伯利亚松林的潜热和感热通量影响较大。这一趋势与上述PBL塔的地面观测结果相吻合。

Analyses on water and energy cycles at a Siberian pine forest are carried out, and the results are compared with those obtained at a Siberian larch forest. There are significant differences of seasonal variations on these cycles between the two forest sites. The parameters for a Jarvis type conductance model are similar to those obtained at the larch forest. There are clear relationships between the parameters in the Jarvis type model using not only our dataset but published datasets and the climatic variables using global grid datasets. This result suggests that physiological responses might be similar under same climatic conditions in spite of different vegetation types.Water cycles characteristics are investigated in a 0-order valley. Evapotranspiration from forest floors are strongly affected by spatial distributions of wind speed when soil moisture is high. On the other hand, understory evapotranspiration is affected by not only wind speed but also the spatial distribution of evaporation efficiency controlled by soil moisture under dry soil condition.The spatial and temporal distributions of latent and sensible heat fluxes in the lower atmospheric boundary layer are examined using a airplane. The results show that local circulation affects strongly the latent and sensible heat fluxes over the Siberian pine forest. This tendency agrees with the results obtained by the ground observation using a PBL tower mentioned above.